In this paper at first a very brief introduction of the history of carbocationic polymerization was given.The slow development in a period of the past 30~40 years was attributed to its high reactivity.The breakthrough began with the clear understanding of the nature of initiation reaction and the essence of modern carbocationic polymerization was to bring the initiation

propagation and termination under control.The recent progress of carbocationic polymerization is in close connection with macromolecular engineering

especially by living carbocationic polymerization(LCCP) .A few examples of macromolecular engineering by "INIFER" and LCCP were presented. Finally

the trend and problem met in this field are advanced.